BIG PINE KEY, Fla. -- In Chris Bergh's neighborhood, the difference between no man's land and lush forest is a five-minute walk.

At the end of one street, 5 feet above sea level, endangered Key deer and rabbits roam past driveways before darting behind thick pine trees lining both sides of the road. Behind the green walls, they slurp from drinking pools fed by an ample supply of fresh water underneath the ground.

As the road gradually slopes downward toward 1 foot above sea level, the pine trees get sparser and wildlife disappears. The shrubby landscape thrives on salt water that seeped through the ground or came from storms, killing off or driving away much of the freshwater ecosystem.

Bergh stopped at the end of the road, where the landscape turns into a mangrove-filled marsh. The only reminder of the pine tree forest that once grew there is a white stump.

"As the sea rises and the salt water keeps coming in, the rest of the area eventually is going to look like this marsh," said Bergh, a director at the Nature Conservancy. "It's just a matter of time."

The future inundation of Big Pine Key is one of many issues that Bergh said he hopes are addressed as part of Monroe County's first-ever climate action plan, set to be released this fall.

The county is the southernmost in the United States, with acreage that is 73 percent water over its 3,737 square miles. It covers portions of the Florida Everglades and the Big Cypress National Preserve, but most of its population of 74,000 resides in the Keys, which are connected by a single highway. Climate change models predict that much of the area could be underwater eventually because of sea-level rise, a process fueled by rising temperatures.

Bergh is the vice chairman of a 11-person advisory committee of city officials, county representatives, environmentalists and other appointed members tasked with providing recommendations on climate change to Monroe's Board of County Commissioners, the Keys' governing body. The commissioners can in turn implement the document in the entire county -- if they approve it -- via their control over agency staff and spending.

Putting the plan together involves hours of meetings, as the committee considers everything from controlling garbage emissions to encouraging planting of native flowers. Florida's "sunshine laws" force them to try to maximize their time, as they are allowed to communicate on the details only in publicly advertised forums.

The draft plan is not meant to be a regulatory framework far in the weeds or a legal mandate. Instead, it makes broad suggestions, such as "provide support to implement water conservation measures."

Will a climate action plan survive?
Even so, officials here say the climate action plan could make a big difference in whether the Florida Keys sit completely vulnerable to the impacts of rising temperatures. Among other things, the county controls zoning regulations, and any changes on how high things are built, and where they are built, likely will have roots in the final document.

"The plan is absolutely critical for keeping climate change on the county agenda," said Michael Roberts, an official in the county Growth Management Division.

At a meeting of the climate change advisory committee in June, officials explained how the action plan meetings -- which have occurred for the past year -- are already driving policy.

Alison Higgins, sustainability coordinator for Key West, said the process prompted her to add climate change considerations to the city's 10-year review of its comprehensive plan, which governs land regulations. The framework will be voted on in October. The seemingly small language changes could determine whether everything from shopping malls to roads consider sea-level rise when undergoing construction.

"There was previously nothing in the comprehensive plan about climate change or greenhouse gases," she said.

Similarly, officials here are under a state mandate to upgrade the Keys' entire wastewater system to advanced treatment plants by 2015. It's a $150 million expenditure eating up much of the county budget.

As the wastewater network heads into its final design this fall, there are discussions about raising wastewater pumps higher in the lower Keys, to make sure salt water doesn't seep into the sewage system in the future. The plan in its current form says "all new and significantly renovated roads, parks, pump stations, filled lots, towers, etc., shall have the grade elevated above the lands' projected sea level for the expected life of the infrastructure."

Kevin Wilson, an engineer in the Monroe County Public Works & Engineering Division, said consideration of the height of wastewater pumps is important because salt water flooding into them could wreak havoc with bacteria designed to break down sewage sludge.

"Wastewater has to come first," County Commissioner Sylvia Murphy said at the recent meeting. The wastewater upgrade is such a huge expenditure that it is the obvious first choice to direct efforts about climate change, she added.

Low-level burning
In Big Pine Key, there is no viable way to prevent seawater from seeping through the porous geology and contaminating the underground freshwater pool that feeds pine forests and deer. The action plan aims to address part of the problem with a "natural systems" section that calls for "low intensity fire regime in fire-dependent uplands and wetlands of the lower Keys."

That essentially is a push for more low-level burning of vulnerable trees, a process that makes them naturally more resilient against storm surges. Controlled burning every decade or so helps clear out leaf litter that gathers on the ground, Bergh explained.

That clearing of litter through fire in turn prevents pine tree roots from migrating upward toward the nutrient-rich litter piles. With their roots tapping into the underground freshwater lens, they are less likely to die from salt water flowing in from heavy rains, he said.

In Bergh's neighborhood, the Fish and Wildlife Service would have to oversee any such burning, as it controls most of the area as part of the National Key Deer Refuge. Many of the pine tree forests in the Keys have not experienced any natural burning for decades, creating a huge amount of buildup on the ground, he said.

"The plan is one way to say, 'Hey, Fish and Wildlife Service, the county thinks this is something you should consider,'" Bergh said. About 60 percent of the Keys is public land, so part of the focus of the climate change advisory committee is to educate and reach out to federal and state agencies.

Federal officials say increased low-level burning is being looked at as part of the service's overall modeling of future climate change impacts. However, there are multiple jurisdictional and social "constraints" to burning more, said Phillip Hughes, an ecologist at the Florida Keys National Wildlife Refuges Complex. Those include the concerns of homeowners leery of increased fire in their neighborhoods.

David Bender, a botanist in the South Florida Ecological Services Office, said the county could play a huge role by buying and conserving land adjacent to public areas. The Keys contain so many species that are found only in this part of Florida that the county will be needed to help create land corridors for plants and animals to move to higher elevations, he explained.

The Fish and Wildlife Service, for example, is helping fund the replanting of Key tree-cactus in the islands that are threatened with extinction because of saltwater intrusion increasingly tainting the soil. This summer, 72 cactuses were planted in the Keys at high ground to try to boost their long-term survival, Bender said.

With climate change, this problem with freshwater-dependent native species is only going to increase, he said. The reintroduction in this case involved state land, but with other species, it will inevitably involve county land, he said.

Sea level rises as budget sinks
The action plan provides a framework for these kind of climate refuges, stating that the Monroe County Land Authority should place "a high priority on purchasing natural areas for conservation purposes."

How much any of these ideas will be implemented is an open question. Monroe County, like many counties around the country, is strapped for cash. The 2012 county budget was $319 million.

As a reference point, the county Public Works & Engineering Division's Wilson said it could cost hundreds of millions of dollars to outfit the entire Florida Keys with stormwater pumps that force water down drains during storms, one option for predicted heavier rainfalls with climate change.

Simultaneously, the county is getting less revenue from state and local gas taxes, said George Neugent, one of the five county commissioners.

It is currently funding many of its projects, including the wastewater revamp, with a 1-cent infrastructure sales tax that may expire, depending on whether Monroe County voters approve its extension in November elections. After that, the next priority for use of the sales tax money is roads and bridges in need of repair, Comissioner Murphy said at the advisory committee meeting.

"Don't even think of trying to do anything else with that money," she told the committee members.

Real estate community prefers 'quiet'
But it is those already planned projects that provide a golden -- and often inexpensive -- opportunity for the action plan, Bergh said. As the county resurfaces roads in coming years with money already allocated, he said, it should think about adding culverts so threatened wildlife can more easily move around.

There are also inexpensive ways to restore wetlands through activities such as plugging ditches, he said.

Additionally, he said, research is going to be extremely important. The county has a basic understanding of the most flood-prone areas, based on land elevation data. But it has not done a thorough analysis of natural infrastructure, such as offshore coral reefs and sand barriers, that could play a major role in holding back water from storm surges and rising seas.

"We need to do that analysis and overlay it with our current zoning," Bergh said.

The fate of the action plan may depend on the public's reaction in hearings and time constraints of the county governing schedule. Murphy and others have urged the advisory committee to narrow things down to six or so main points, to not overwhelm the Board of Commissioners. That raises a lot of questions in coming months about what will be emphasized and what will be taken out.

There is no guarantee, either, that the plan will be implemented if it is adopted.

Neugent said public opinion and a "lack of passion" among some members of the board are still obstacles.

The islands are not yet experiencing constant flooding problems, making it difficult to force climate change to the top of the agenda on a day-to-day basis, he said.

The real estate community, for one, is not thinking extensively about climate change and does not want the board to alarm people, he said.

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